You can have customers without product market fit.

A product that hasnt found PMF could be a solution looking for a problem, or it might solve a true problem but that problem isn't important, durable, or (crucially) common enough to sustain a business.

So OP was saying that Lightstream Studios made some great stuff, but that ultimately the problem they were solving wasnt durable or widespread enough for the market to sustain the business they had built.

Background on Lighstream Studios is they did a streamer setup in the cloud, so you didnt have to run OBS locally. A lot of people seemed to want that at the time, especially console gamers, but the market changed around them. Consoles are way better at streaming without any other stuff now, and PC gamers largely settled on running OBS (for free) on their own existing hardware. They had like 17k paying customers at one point, so customers wasnt the smoking gun here.

There are plenty of companies (successful ones) that I’d argue don’t have PMF, but have plenty of customers (ex Palantir)

The client on the other hand I would guess is running it's code as root, or at least something with full GPU access.

The OP didn’t intercept rtmp url, they intercepted the discovery endpoint.

https://kiwipi.com/blog/rk3588-hdmi-in-test/